1. Field of the Invention
This application concerns a pneumatic apparatus to test an oil pump for an internal combustion engine of the type mounted to the front of the engine and directly driven by the front end of the engine crankshaft. The pump is tested under simulated engine conditions by rotation of the pump and application of pressured air. Resultant air flow characteristics are measured to determine the pump's acceptability based on flow rates.
1. Description of Related Art
Currently oil pumps are tested using actual oil. By this test, characteristics such as flow rate and leakage can be observed. However, testing with actual oil creates a significant "housekeeping" problem as the procedure is messy. Further, a relatively long cycle time is needed to test using oil. Also, the greater investment for equipment and the loss of testing oil with each pump tested, increases testing costs.
The following prior art was uncovered by a pre-examination search.
The U.S. Pat. No. 4,125,014 discloses a test assembly for oil pumps using hydraulic fluid (oil) to test a pump already installed in an engine. This test assembly would prevent some of the problems mentioned above but would identify an unacceptable pump only after installation not before which is desirable.
The foreign patent JA 03-10139(1/991) discloses a test for testing mating of bearing members using a high pressure air feed and measuring the exhaust or outlet pressure.
The U.S. Pat. Nos. 2,671,345 and 3,452,591 disclose testing carburetors and fuel pumps, respectively, using pressurized air rather than liquid.
Other features and advantages of the subject pneumatic oil pump functional test will become more apparent from the following: